A key switch structure which enables a reduction in the width of the key switch. A key switch structure comprises a first support member (22), a second support member (23), and a third support member which are arranged independently of each other, the first support member (22) having rotation pins (22d, 22e) and slide pins (22a, 22b), the second support member (23) having rotation pins (23e, 23f) and a circular columnar slide section (23a), the third support member having front end sections (24d, 24e), which are slidably held, and a support shaft section (24a). A key top (21) is supported by the support members (22, 23, 24) so that the key top (21) can move in the vertical direction. The length of at least one side of each of the support members is set to be less than or equal to the mounting diameter of a rubber dome (27).
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2. A key switch structure in which a key top is pushed-down and makes contact with a conductor, and the key top is returned to an original position by a restoring member, the key switch structure comprising:
a plurality of supporting members that support the key top so as to be movable vertically;
wherein the length of at least one side of each of the plurality of supporting members is less than or equal to a placement diameter of the restoring member;
wherein the key switch structure further comprises a first restricting portion that restricts positional offset, in a predetermined direction, of at least one supporting member among the plurality of supporting members, and a second restricting portion that restricts positional offset, in the predetermined direction, of the key top with respect to the at least one supporting member;
wherein the key switch structure further comprises a third restricting portion that restricts positional offset, in a direction that is different than the predetermined direction, of a supporting member other than the at least one supporting member among the plurality of supporting members, and a fourth restricting portion that restricts positional offset, in the direction that is different than the predetermined direction, of the key top with respect to the supporting member other than the at least one supporting member;
wherein the first and second restricting portions also restrict positional offsets of the at least one supporting member and the key top, respectively, in a direction opposite to the predetermined direction;
wherein the third and fourth restricting portions also restrict positional offsets of the other one of the supporting members and the key top, respectively, in a direction opposite to the direction that is different than the predetermined direction; and
wherein the third restricting portion is configured by inner sides of both side end portions of the other one of the supporting members abutting a holder, and the fourth restricting portion is configured by fixing walls formed at the key top abutting end portions of the other one of the supporting members.
1. A key switch structure in which a key top is pushed-down and makes contact with a conductor, and the key top is returned to an original position by a restoring member, the key switch structure comprising:
a plurality of supporting members that support the key top so as to be movable vertically;
wherein the length of at least one side of each of the plurality of supporting members is less than or equal to a placement diameter of the restoring member;
wherein the key switch structure further comprises a first restricting portion that restricts positional offset, in a predetermined direction, of at least one supporting member among the plurality of supporting members, and a second restricting portion that restricts positional offset, in the predetermined direction, of the key top with respect to the at least one supporting member;
wherein the key switch structure further comprises a third restricting portion that restricts positional offset, in a direction that is different than the predetermined direction, of a supporting member other than the at least one supporting member among the plurality of supporting members, and a fourth restricting portion that restricts positional offset, in the direction that is different than the predetermined direction, of the key top with respect to the supporting member other than the at least one supporting member;
wherein the first and second restricting portions also restrict positional offsets of the at least one supporting member and the key top, respectively, in a direction opposite to the predetermined direction;
wherein the third and fourth restricting portions also restrict positional offsets of the other one of the supporting members and the key top, respectively, in a direction opposite to the direction that is different than the predetermined direction; and
wherein the first restricting portion is configured by positions of distal end portions of rotating pins of one of the supporting members being restricted by deep walls of groove portions in a holder, and the second restricting portion is configured by positions of sliding/holding portions provided at the key top being restricted by distal end portions of sliding pins of the one of the supporting members.
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The present invention relates to a structure of a key switch that is used in a personal computer or the like, and in particular, relates to a key switch structure that is used in thin, compact personal computers.
Conventionally, in a keyboard that is used in a portable personal computer or the like, the so-called operability, in which a key top descends without tilting regardless of which portion of the key top is pushed, is ensured. To this end, a conventional key switch structure has a link mechanism at the lower portion of the key top. For example, there is the structure disclosed in Japanese Patent Application Laid-Open No. 2001-229764 as a key switch structure having a link mechanism at the lower portion of the key top.
The conventional key switch structure, that is equipped with a link mechanism and is disclosed in the aforementioned document, is shown in
Further, an embossed portion 17a that projects upward is formed at the back plate 17, and this embossed portion 17a is set in a through-hole 16b that is formed in the membrane sheet 16. Further, a pin 15a for welding is formed at the lower portion of the holder 15, and this pin 15a for welding is set in a hole 17b that is formed in the embossed portion 17a of the back plate 17. In the state in which the pin 15a for welding is set in the hole 17b, the back plate 17 is welded to the holder 15 with the membrane sheet 16 sandwiched therebetween.
In the above-described key switch structure, even if an end portion of the key top 11 is pushed-down, the key top 11 descends while the horizontal state is maintained by the link mechanism that is formed from the first, second link members 12, 13. For example, when the position of the end portion of the key top 11 shown by arrow A in
However, in the above-described, conventional key switch structure, the link mechanism, which is structured by the first link member and the second link member, is disposed so as to surround the rubber dome. Namely, portions, where the first link member and the second link member overlap in the horizontal direction, are positioned at both sides of the rubber dome. Therefore, wider spaces for placing the link mechanism are needed at both sides of the rubber dome, and there is the problem that it is difficult to make the width of the key switch narrow.
Further, in the conventional key switch structure, among the first link member and the second link member that structure the link mechanism, the holder side of one link member is made to be slidable, and the key top side of the other link member is made to be slidable. Therefore, there is the problem that, when the key top is pushed-down, the key top descends while becoming offset in the horizontal direction.
In order to overcome the above-described problems, in a key switch structure in which a key top is pushed-down and makes a contact conductive, and the key top is returned to an original position by a restoring member, the present invention has the feature of comprising plural supporting members that support the key top so as to be movable vertically, wherein at least one side of each of the plural supporting members is less than or equal to a placement diameter of the restoring member. A holding portion, that holds the key top in a horizontal state when not pushed-down, may be provided at at least one supporting member among the plurality of supporting members. Further, there may be provided a first restricting portion that restricts positional offset, in a predetermined direction, of at least one supporting member among the plurality of supporting members, and a second restricting portion that restricts positional offset, in the predetermined direction, of the key top with respect to the at least one supporting member.
In accordance with the present invention, a structure in which the supporting members are not disposed at the periphery of the restoring member is possible, and a narrow-width key switch can be provided. Further, by providing the holding portion, that holds the key top, when not pushed-down, in a horizontal state, at at least one supporting member among the plural supporting members, the key top, when not pushed down, can be held in a horizontal state. Further, by providing the first restricting portion that restricts positional offset, in a predetermined direction, of at least one supporting member among the plural supporting members, and the second restricting portion that restricts positional offset, in the predetermined direction, of the key top with respect to the at least one supporting member, there can be made to be a structure in which horizontal direction offset of the key top does not arise when the key top is pushed-down.
Embodiments of the present invention are described hereinafter in accordance with the drawings.
Embodiment 1
In
A pair of first sliding/holding portions 31a, 31b, a pair of second sliding/holding portions 32a, 32b, and a pair of rotating/holding portions 33a, 33b are provided at the bottom surface of the key top 21. As shown in
Rotating pins 22d, 22e are formed at the both side surfaces of the other end portion of the first supporting member 22, and the rotating pins 22d, 22e respectively are rotatably fit-into groove portions 25a, 25b that are formed in the first holder 25. The position of the first supporting member 22 in the arrow Y direction shown in
As shown in
In
As can be understood from
The pair of rotating/holding portions 33a, 33b rotatably hold the third supporting member 24. Namely, as shown in
The third supporting member 24 is approximately formed in a substantial U-shape, and, in addition to the pivot portion 24a, has side end portions 24b, 24c and distal end portions 24d, 24e. As shown in
As shown in
As shown in
In this case, in the present embodiment, L1, L2, L3 are all set to be less than or equal to the diameter L of the rubber dome 27 (L1≦L, L2≦L, L3≦L). Due thereto, the supporting members can be disposed without being hampered by the diameter of the rubber dome 27. Further, by making the supporting members be smaller than the diameter of the rubber dome 27, the supporting members themselves are made small, and, due thereto, the size of the key switch itself can be made to be small. Moreover, the shape of the key switch also can be addressed flexibly.
Operation of the present embodiment is described next. The state before the key top 21 is pushed-down is the state shown in
When, from this state, the key top 21 is pushed-down in the direction of the arrow shown in
Further, the second supporting member 23 rotates in the counterclockwise direction in
The third supporting member 24 rotates, from the state shown in
When the above-described series of operations are carried out simultaneously, as shown in
Further, as shown in
As shown in
The key top 21 maintains a horizontal state, and descends in the vertical direction. Due thereto, the rubber dome 27 is pushed by the reverse surface of the key top 21 and buckles. The projecting portion 27a of the rubber dome 27 that has buckled pushes the unillustrated contact portion of the membrane sheet 28, and the key switch becomes electrically conductive. When the operator eliminates the push-down force with respect to the key top 21, the key top 21 is pushed-upward by the restoring force of the rubber dome 27 and moves upward, and accompanying this, the first supporting member 22, the second supporting member 23 and the third supporting member 24 respectively carry out operations in directions opposite to those at the time of pushing-down, and the key top 21 moves upward while maintaining the horizontal state.
As described above, in accordance with embodiment 1, at least one side of each of the first supporting member 22, the second supporting member 23 and the third supporting member is less than or equal to the placement diameter of the rubber dome 27. Therefore, by placing the supporting members so as to not surround the rubber dome 27, the width of the key switch can be made to be narrow. Further, the size of the rubber dome 27 can be made to be large in proportion to the size of the key top 21, and therefore, lengthening of the stroke of the key switch and extending of the lifespan thereof can be devised. Moreover, the projecting portion 22f and the chamfered portion 22c, that are for restricting the angle of rotation, are formed at the first supporting member 22, and further, the chamfered portion 23g is formed at the second supporting member 23 as well. Therefore, when the key top 21 is not pushed-down, the key top 21 can reliably maintain a horizontal state. Moreover, because the key switch structure has functions for preventing positional offset of the key top 21, when the key top 21 is pushed-down, the key top 21 descends in the vertical direction without the position thereof being offset in either the X direction or the Y direction.
Embodiment 2
Embodiment 2 is described next.
The planar shape of the key top 41 is not rectangular, and is a curved shape. The first supporting member 42 is a similar shape as and is similarly rotatable as the first supporting member 22 of embodiment 1, but a rotating shaft 42a thereof is displaced, by angle θ1 with respect to the arrow Y direction, in a direction that runs along the shape of the key top 41. Accompanying this, groove portions 45a, 45b, 45c of the first holder 45 are formed so as to be inclined by the angle θ1 with respect to the arrow Y direction, as compared with those of embodiment 1, and further, first sliding/holding portions 51a, 51b also are disposed so as to be inclined by angle θ1 with respect to the arrow Y direction.
Further, the second supporting member 43 as well is a similar shape as and is similarly rotatable as the second supporting member 23 of embodiment 1, but a rotating shaft 43a thereof is displaced, by angle θ2 with respect to the arrow Y direction, in a direction that runs along the shape of the key top 41. Accompanying this, groove portions 46a, 46b of the second holder 26 are formed so as to be inclined by the angle θ2 with respect to the arrow Y direction, as compared with those of embodiment 1, and second sliding/holding portions 52a, 52b also are disposed so as to be inclined by angle θ2 with respect to the arrow Y direction. The other structures are similar to embodiment 1.
In embodiment 2 that has the above-described structure, the operation due to the pushing-down of the key top 41 is similar to above-described embodiment 1. In embodiment 2, by disposing the first supporting member 42 and the second supporting member 43 at an incline, the first supporting member 42 and the second supporting member 43 can be disposed along the shape of the key top 41. By disposing the first supporting member 42 and the second supporting member 43 along the shape of the key top 41, regardless of what portion of the top surface of the key top 41 is pushed-down, the key top 41 can descend while maintaining a horizontal state, without tilting.
Although the above-described respective embodiments describe examples in which three of the supporting members are provided, in the present invention, the number of supporting members is not limited to three, and may be two or four or another number. Further, the above-described embodiments illustrate examples in which supporting members of three types of shapes that are plate-shaped (the first supporting member), prism shaped (the second supporting member) and round bar shaped (the third supporting member) are used as the shapes of the supporting members, but what shape of supporting member is to be used can be selected in accordance with the size and the shape of the key switch. For example, when the key switch is large, plate-shaped supporting members can be used, and, when the key switch is long and narrow, round bar shaped supporting members can be used.
Moreover, in the above-described embodiments, the first supporting member and the second supporting member are crank-shaped, and by making them be crank-shaped, flexibility is provided to the arrangement of the supporting members, and the supporting members can be set in an arrangement that better corresponds to the shape of the key switch. Namely, the crank shapes of the supporting members can be changed flexibly in accordance with the shape of the key switch and the placed positions.
Industrial Applicability
The key switch structure of the present invention is used in keyboard devices that are used as input devices in information processors, measuring devices, medical equipment, and the like, and in particular, is used in keyboard devices that serve as input devices for compact, thin personal computers.
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Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
May 09 2011 | Oki Electric Industry Co., Ltd. | (assignment on the face of the patent) | / | |||
Nov 15 2012 | YAMADA, SHIGERU | OKI ELECTRIC INDUSTRY CO , LTD | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 029386 | /0803 | |
Aug 07 2017 | OKI ELECTRIC INDUSTRY CO , LTD | JIANGSU TRANSIMAGE TECHNOLOGY CO , LTD | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 043762 | /0340 |
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